Schneider Electric (Barber Colman) 2372-351 Relay

The Schneider Electric (Barber Colman) 2372-351 Relay is a precision-engineered pneumatic low pressure selector relay designed for advanced HVACR control loops that require the selection and transmission of the lower of two proportional input signals. As a veteran in the field, you recognize this Barber Colman 2372-351 as a reliable, non-adjustable component built for precise repeatability in complex air systems. Constructed from durable glass-filled nylon, this unit functions seamlessly with a 20 psig main air operating pressure and can handle a maximum of 30 psig. When utilized as a volume booster relay, it delivers a robust 29 SCIM at the main port while maintaining high sensitivity with 1.5 SCIM at the signal port. The low pressure selector features 3/16" barbed nipples specifically for 1/4" O.D. tubing, ensuring a secure, leak-free connection. Its compact, lightweight design facilitates "in-line" mounting, often eliminating the need for additional brackets while providing consistent proportional action across a wide ambient temperature range of 35 to 140°F.

• Precise Signal Selection: Automatically transmits the lower of two pneumatic signals for accurate sequence control and safety interlocking.
• Dual-Function Capability: Operates efficiently as either a low pressure selector or a pneumatic volume booster depending on port configuration.
• Easy In-Line Installation: Compact 1-13/16" diameter allows for mounting directly supported by pneumatic tubing, saving time in cramped enclosures.
• Industrial Durability: Glass-filled nylon construction ensures stability in harsh mechanical rooms and resists the degradation common in HVACR environments.
• Versatile Compatibility: Standard fittings for 1/4" O.D. polyethylene tubing make it a drop-in replacement for various legacy Barber Colman and Schneider systems.

How do I plumb the 2372-351 when used as a low pressure selector?
For low pressure selection, connect your two signal lines to the "S" and "M" ports. The output signal will then be transmitted from the "B" port to your final control device, such as an actuator or valve.

Can this relay be used with non-air mediums?
No. This pneumatic signal relay is designed strictly for clean, dry, oil-free control air. Using other mediums can compromise the internal diaphragms and lead to control failure.

Does the mounting orientation affect performance?
The 2372-351 is designed to be position-insensitive; it will operate accurately in any mounting orientation, provided the connections are secure and the tubing is not kinked.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.